The invention is directed to a novel method of and apparatus for introducing pulverulent material into tires, specifically radial tires of wheel assemblies of passenger and truck vehicles and aircraft. The method and apparatus are specifically directed to utilizing pulverulent polymeric synthetic plastic material and introducing the same into a tire through an associated tire valve to effect dynamic balancing of the associated wheel assembly and equalization of radialand lateral load force variations as the wheel assembly is subject to impact forces during rotation thereof along a surface, such as a road, airfield or the like.
The specifics of the method of balancing a wheel assembly and equalizing radial and lateral load force variations in accordance with injection of pulverulent polymeric synthetic plastic material into a tire are fully disclosed in U.S. Pat. No. 5,073,217 in the name of Robert D. Fogal issued on Dec. 17, 1991. The specifics of the pulverulent material, as set forth in the latter patent and the screen size ranges, pulverulent material weight ranges and the weight ranges for a specific range of tires, as also set forth in the latter-identified patent, are all incorporated herein by reference.
The term, "pulverulent polymeric material" as used herein denotes a solid material in pulverulent or particulate form which comprises a polymer (which may be either a homopolymer or a copolymer) and which may comprise other constituents, i.e., fillers and additives. The preferred pulverulent polymeric material, as set forth in U.S. Pat. No. 5,073,217, comprises a major portion (70% by weight) of a polymeric material, specifically, a polymerized urea formaldehyde thermoset resin having a particle size range and other physical characteristics as set forth in U.S. Pat. No. 5,073,217, and minor portions of constituents, i.e, 25% by weight cellulosic filler and 2% pigments and additives. This material has a specific gravity of 1.47-1.52 and a bulk density of 58-60 pounds per cubic foot (0.93-0.96 grams per cubic centimeter).